US10725088B2 - Apparatus for estimating lifetime of the SPD using discharge characteristics of the MOV - Google Patents
Apparatus for estimating lifetime of the SPD using discharge characteristics of the MOV Download PDFInfo
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- US10725088B2 US10725088B2 US15/989,723 US201815989723A US10725088B2 US 10725088 B2 US10725088 B2 US 10725088B2 US 201815989723 A US201815989723 A US 201815989723A US 10725088 B2 US10725088 B2 US 10725088B2
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- 238000012360 testing method Methods 0.000 claims abstract description 46
- 230000002159 abnormal effect Effects 0.000 claims abstract description 29
- 238000005259 measurement Methods 0.000 claims abstract description 23
- 230000001681 protective effect Effects 0.000 claims abstract description 5
- 229910044991 metal oxide Inorganic materials 0.000 claims abstract description 3
- 150000004706 metal oxides Chemical class 0.000 claims abstract description 3
- 230000007935 neutral effect Effects 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000007792 addition Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/26—Testing of individual semiconductor devices
- G01R31/2607—Circuits therefor
- G01R31/2637—Circuits therefor for testing other individual devices
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
- G01R31/14—Circuits therefor, e.g. for generating test voltages, sensing circuits
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/165—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
- G01R31/1227—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials
- G01R31/1236—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials of surge arresters
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/26—Testing of individual semiconductor devices
- G01R31/2601—Apparatus or methods therefor
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/28—Testing of electronic circuits, e.g. by signal tracer
- G01R31/282—Testing of electronic circuits specially adapted for particular applications not provided for elsewhere
- G01R31/2827—Testing of electronic protection circuits
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
- G01R31/3277—Testing of circuit interrupters, switches or circuit-breakers of low voltage devices, e.g. domestic or industrial devices, such as motor protections, relays, rotation switches
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01C—RESISTORS
- H01C7/00—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material
- H01C7/10—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material voltage responsive, i.e. varistors
- H01C7/105—Varistor cores
- H01C7/108—Metal oxide
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01C—RESISTORS
- H01C7/00—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material
- H01C7/10—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material voltage responsive, i.e. varistors
- H01C7/12—Overvoltage protection resistors
- H01C7/126—Means for protecting against excessive pressure or for disconnecting in case of failure
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H9/00—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
- H02H9/04—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage
- H02H9/042—Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage comprising means to limit the absorbed power or indicate damaged over-voltage protection device
Definitions
- the present invention relates to an apparatus for estimating the lifetime of a surge protective device (SPD) using the discharge characteristics of a metal oxide varistor (MOV), which can check the damage state of the MOV by applying an impulse voltage to the MOV and checking the discharge current of the MOV.
- SPD surge protective device
- MOV metal oxide varistor
- a known overvoltage protective device includes an SPD for preventing an overvoltage from being applied to an electronic device due to surge.
- the SPD includes various elements, such as an MOV.
- the SPD is gradually damaged when an overvoltage, such as surge, continues to flow into the SPD, and stops operating at a specific point of time. Accordingly, an external electronic device connected to the SPD cannot be normally protected, and an electronic device may be directly damaged by a transient voltage/current.
- Korean Patent No. 10-1253229 the short circuit of an MOV is detected and an SPD indicates the short circuit using an LED.
- the conventional technology has a problem in that equipment is damaged when surge is received because whether the SPD has failed cannot be checked if the SPD is not shorted, but is partially damaged.
- Korean Patent No. 10-1303202 received energy is checked based on the amount and number of surge currents, and a failure rate of an SPD is estimated.
- the conventional technology has problems in that an error rate of input surge current measurement becomes an important factor and an excellent CT must be provided for the error rate.
- An embodiment of the present invention provides an apparatus for estimating the lifetime of an SPD using the discharge characteristics of an MOV, which can check the damage state of the MOV by applying an impulse voltage to the MOV and checking the discharge current of the MOV.
- An apparatus for estimating the lifetime of an SPD using the discharge characteristics of an MOV includes an MOV 100 having an input terminal 11 and an output terminal 12 ; an impulse voltage application unit 20 having one end connected to external power supplied to an SPD and the other end selectively connected to the input terminal 11 of the MOV, wherein when the MOV is tested, the impulse voltage application unit 20 applies an impulse voltage for an MOV test to the input terminal 11 of the MOV; a discharge current measurement unit 30 selectively connected to the output terminal 12 of the MOV and measuring a discharge current output from the output terminal 12 of the MOV when the MOV is tested; a first switching unit 40 connecting a power line to the input terminal 11 of the MOV when the MOV is a normal mode and selectively connecting the impulse voltage application unit 20 to the input terminal 11 of the MOV when the MOV is an MOV test mode; a second switching unit 50 connecting a ground line to the output terminal 12 of the MOV in the normal mode and selectively connecting the discharge current measurement unit 30 to the output terminal 12 of the MOV
- the discharge current measurement unit 30 stores the measured discharge current.
- the MOV test management unit 60 stores a test cycle so that the MOV 10 is regularly tested.
- the MOV test management unit 60 receives a test mode signal of the MOV 10 from an external management center and controls the first switching unit 40 and the second switching unit 50 .
- the MOV abnormal signal differently generates a caution signal or a warning signal depending on the degree that the discharge current deviates from the reference current.
- the apparatus further includes an external notification unit 90 providing an MOV abnormal signal to a wireless terminal of a registered administrator or a management center along with unique ID information of the SPD when the MOV abnormal signal is generated by the discharge current check unit 70 .
- an external notification unit 90 providing an MOV abnormal signal to a wireless terminal of a registered administrator or a management center along with unique ID information of the SPD when the MOV abnormal signal is generated by the discharge current check unit 70 .
- the external notification unit 90 further provides the discharge current measured by the discharge current measurement unit 30 .
- FIG. 1 is a block diagram of an apparatus for estimating the lifetime of an SPD using the discharge characteristics of an MOV according to an embodiment of the present invention.
- FIG. 2 is a flowchart showing an operational process of the apparatus for estimating the lifetime of an SPD using the discharge characteristics of an MOV according to an embodiment of the present invention.
- an overvoltage/current is input to one side of the apparatus, and an SPD to which an external electronic device is connected is located on the other side of the apparatus.
- the apparatus for estimating the lifetime of an SPD includes an MOV 10 , an impulse voltage application unit 20 , a discharge current measurement unit 30 , a first switching unit 40 , a second switching unit 50 , an MOV test management unit 60 , a discharge current check unit 70 , an MOV state display unit 80 , and an external notification unit 90 .
- the MOV 10 is used for protection against a surge voltage or overvoltage, and includes an input terminal 11 and an output terminal 12 . When power of a specific level or more is applied through the input terminal 11 , the power is conducted to the ground through the output terminal 12 . At normal times, the MOV 10 is connected to a power line (L line) and a neutral line (N line) or connected to the power line (L line) and a ground line (G line) or connected to the neutral line (N line) and a ground line (G line), thus being capable of detecting all of overvoltage received through the lines.
- L line power line
- N line neutral line
- G line ground line
- G line ground line
- the impulse voltage application unit 20 has one end connected to external power supplied to an SPD and the other end selectively connected to the input terminal 11 of the MOV.
- the impulse voltage application unit 20 applies an impulse voltage for an MOV test to the input terminal 11 of the MOV.
- the impulse voltage application unit 20 can check a discharge current output from the output terminal of the MOV.
- the impulse voltage application unit 20 can check the replacement time of the MOV.
- the discharge current measurement unit 30 is selectively connected to the output terminal 12 of the MOV, and measures a discharge current output from the output terminal 12 of the MOV when the MOV is tested. At this time, the discharge current measurement unit 30 may store the measured discharge current in a discharge current DB 31 .
- the first switching unit 40 When the MOV 10 is a normal mode, the first switching unit 40 connects the power line to the input terminal 11 of the MOV.
- the MOV 10 When the MOV 10 is an MOV test mode, the first switching unit 40 selectively connects the impulse voltage application unit 20 to the input terminal 11 of the MOV. In the normal mode, the first switching unit 40 connects the power line to the input terminal 11 of the MOV so that the MOV 10 can handle a surge current. In the MOV test mode, the power line connected to the input terminal 11 of the MOV is blocked, and the input terminal 11 of the MOV is connected to the impulse voltage application unit 20 .
- the second switching unit 50 connects the ground line to the output terminal 12 of the MOV.
- the second switching unit 50 selectively connects the discharge current measurement unit 30 to the output terminal 12 of the MOV.
- the second switching unit 50 connects the output terminal 12 of the MOV to the ground line so that the MOV 10 can handle a surge current.
- the output terminal 12 of the MOV is connected to the discharge current measurement unit 30 .
- the MOV test management unit 60 provides information about the normal mode or test mode of the MOV 10 to the first switching unit 40 and the second switching unit 50 .
- the MOV test management unit 60 performs control so that the impulse voltage application unit 20 generates an impulse voltage.
- the MOV test management unit 60 includes a test cycle DB 61 in which a month, week, date, and time are stored so that the MOV 10 is regularly tested. Accordingly, the MOV test management unit 60 controls the first switching unit 40 and the second switching unit 50 by periodically generating a test mode signal or may receive the test mode signal of the MOV 10 from an external management center and control the first switching unit 40 and the second switching unit 50 .
- the discharge current check unit 70 compares a discharge current measured by the discharge current measurement unit 30 with a reference current, and generates an MOV abnormal signal when the measured discharge current is lower than the reference current. That is, when the MOV is used and surge is input, a discharge current corresponding to an impulse voltage when the MOV is the test mode is gradually lowered. When the discharge current is lower than a reference discharge current, the discharge current check unit 70 determines that the MOV has been damaged and generates the MOV abnormal signal. The discharge current check unit 70 may differently generate a caution signal or a warning signal depending on the degree that the measured discharge current has deviated from the reference discharge current. Accordingly, the state of the MOV 10 can be checked based on the amount of the discharge current.
- the MOV state display unit 80 is positioned on an external surface of the SPD, and displays the MOV abnormal signal so that it can be checked outside when the MOV abnormal signal is generated by the discharge current check unit 70 .
- the MOV state display unit 80 may be an LED.
- the MOV state display unit 80 may be displayed in green when the MOV abnormal signal is not generated, may be displayed in orange when the MOV abnormal signal is the caution signal, and may be displayed in red when the MOV abnormal signal is the warning signal. In this case, the MOV state display unit 80 may display the amount of a discharge current on the external surface of the SPD.
- the external notification unit 90 When the MOV abnormal signal is generated by the discharge current check unit 70 , the external notification unit 90 provides the MOV abnormal signal to the wireless terminal of a registered administrator or a management center along with unique ID information of the SPD. In this case, the external notification unit 90 may also provide a discharge current measured by the discharge current measurement unit 30 . Accordingly, an external management center that manages multiple SPDs can easily check the state of the installation location of the SPD and replace the MOV 10 .
- the MOV test management unit 60 controls the first switching unit 40 and the second switching unit 50 so that the MOV 10 is connected to the power line (L line) and the neutral line (N line), connected to the power line (L line) and the ground line (G line) or connected to the neutral line (N line) and the ground line (G line) so that the MOV 10 of the SPD can handle a surge current, thereby being capable of detecting an overvoltage (S 101 ).
- the MOV test management unit 60 changes the first switching unit 40 and the second switching unit 50 to the MOV test mode (S 102 ). Accordingly, the MOV test management unit 60 connects the impulse voltage application unit 20 to the input terminal 11 of the MOV and connects the discharge current measurement unit 30 to the output terminal 12 of the MOV (S 103 ).
- the discharge current measurement unit 30 connected to the output terminal 12 of the MOV measures a discharge current (S 105 ).
- the discharge current check unit 70 compares the measured discharge current measured with a reference current, and generates the MOV abnormal signal when the measured discharge current is lower than the reference current (S 106 ). In this case, the MOV abnormal signal is classified as a caution signal or a warning signal depending on the degree that the measured discharge current has deviated from the reference current.
- the LED of the MOV state display unit 80 positioned on an external surface of the SPD is displayed so that it can be checked by an administrator (S 107 ).
- the LED is displayed in orange when the MOV abnormal signal is the caution signal, and is displayed in red when the MOV abnormal signal is the warning signal.
- the MOV abnormal signal When the MOV abnormal signal is generated, it is provided to the wireless terminal of a registered administrator or a management center along with unique ID information of the SPD so that the state of the MOV 10 can be checked by the administrator or the management center (S 108 ).
- the apparatus for estimating the lifetime of an SPD using the discharge characteristics of an MOV has an advantage in that it can precisely check the state of the MOV by applying an impulse voltage to the MOV and checking a discharge current of the MOV. That is, if a higher discharge current than that in an initial state is measured in the MOV, it may be seen that the MOV is damaged.
- the L-N or L-G or N-G is connected to the input terminal and output terminal of the MOV so that the MOV can handle a surge current.
- the impulse voltage application unit and the discharge current measurement unit are connected to the input terminal and output terminal of the MOV only when the MOV is tested. Accordingly, there is an advantage in that the MOV can be tested while not affecting the operation of the MOV.
- an error of a discharge current output from the output terminal of the MOV can be minimized compared to a case where a voltage is continuously applied to the MOV because an impulse voltage is applied to the MOV.
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- General Engineering & Computer Science (AREA)
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KR10-2018-0055620 | 2018-05-15 | ||
KR1020180055620A KR102072736B1 (en) | 2018-05-15 | 2018-05-15 | Apparatus for forecasting the lifetime of SPD using discharge characteristic of MOV |
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US20190353694A1 US20190353694A1 (en) | 2019-11-21 |
US10725088B2 true US10725088B2 (en) | 2020-07-28 |
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US15/989,723 Active 2038-11-03 US10725088B2 (en) | 2018-05-15 | 2018-05-25 | Apparatus for estimating lifetime of the SPD using discharge characteristics of the MOV |
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Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
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US10345372B2 (en) * | 2015-04-22 | 2019-07-09 | ASCO Power Technologies L.P. | Devices and methods for surge protection device monitoring |
EP3837747B1 (en) * | 2018-08-13 | 2022-12-07 | The Vollrath Company, LLC | Ac controlled relay drive circuit |
CN112763900B (en) * | 2020-12-25 | 2021-11-19 | 西安交通大学 | MOV state measuring circuit and method for energy consumption branch of hybrid direct current breaker |
CN115588973B (en) * | 2022-11-24 | 2023-03-21 | 苏州浪潮智能科技有限公司 | Transient diode failure monitoring circuit |
Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6477025B1 (en) * | 1999-10-12 | 2002-11-05 | Innovative Technology, Inc. | Surge protection device with thermal protection, current limiting, and failure indication |
US20080218925A1 (en) * | 2005-11-30 | 2008-09-11 | University Of South Florida | Mov failure mode identification |
US7453368B2 (en) * | 2006-02-15 | 2008-11-18 | Hubbell Incorporated | Surge protector life cycle monitor system and method |
US20090207034A1 (en) * | 2007-12-26 | 2009-08-20 | Audiovox Corporation | Home control protection system |
US20090287108A1 (en) | 2008-05-19 | 2009-11-19 | Levy Mark M | System for study and treatment of behavior dysregulation |
KR101253229B1 (en) | 2012-11-05 | 2013-04-16 | 김병학 | Surge protect device for tvs/varistor short detection and communication |
KR101303202B1 (en) | 2012-12-21 | 2013-09-10 | 선광엘티아이(주) | Surge protective device using air gap ct and failure prediction system of spd using it |
US20160028226A1 (en) * | 2014-07-23 | 2016-01-28 | Michael Kuo | Modular surge protection device with status indicator |
US20160313389A1 (en) * | 2015-04-22 | 2016-10-27 | ASCO Power Technologies L.P. | Devices and Methods for Surge Protection Device Monitoring |
US9784785B2 (en) * | 2014-12-09 | 2017-10-10 | Asco Power Technologies, L.P. | Method of detecting metal oxide varistor (MOV) failure within a surge protection device |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR101232092B1 (en) * | 2012-10-15 | 2013-02-12 | (주)옴니엘피에스 | Hybrid impulse current generator |
KR101268355B1 (en) * | 2013-02-15 | 2013-06-04 | 선광엘티아이(주) | Failure prediction system of spd |
KR101324086B1 (en) * | 2013-04-15 | 2013-10-31 | 한국산업은행 | Multi-mode tov testing system |
KR101391823B1 (en) * | 2014-02-07 | 2014-05-07 | 선광엘티아이(주) | Automatically transfer switching overvoltage protection apparatus |
-
2018
- 2018-05-15 KR KR1020180055620A patent/KR102072736B1/en active IP Right Grant
- 2018-05-25 US US15/989,723 patent/US10725088B2/en active Active
Patent Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6477025B1 (en) * | 1999-10-12 | 2002-11-05 | Innovative Technology, Inc. | Surge protection device with thermal protection, current limiting, and failure indication |
US20080218925A1 (en) * | 2005-11-30 | 2008-09-11 | University Of South Florida | Mov failure mode identification |
US7453368B2 (en) * | 2006-02-15 | 2008-11-18 | Hubbell Incorporated | Surge protector life cycle monitor system and method |
US20090207034A1 (en) * | 2007-12-26 | 2009-08-20 | Audiovox Corporation | Home control protection system |
US20090287108A1 (en) | 2008-05-19 | 2009-11-19 | Levy Mark M | System for study and treatment of behavior dysregulation |
KR101253229B1 (en) | 2012-11-05 | 2013-04-16 | 김병학 | Surge protect device for tvs/varistor short detection and communication |
KR101303202B1 (en) | 2012-12-21 | 2013-09-10 | 선광엘티아이(주) | Surge protective device using air gap ct and failure prediction system of spd using it |
US20160028226A1 (en) * | 2014-07-23 | 2016-01-28 | Michael Kuo | Modular surge protection device with status indicator |
US9784785B2 (en) * | 2014-12-09 | 2017-10-10 | Asco Power Technologies, L.P. | Method of detecting metal oxide varistor (MOV) failure within a surge protection device |
US20160313389A1 (en) * | 2015-04-22 | 2016-10-27 | ASCO Power Technologies L.P. | Devices and Methods for Surge Protection Device Monitoring |
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US20190353694A1 (en) | 2019-11-21 |
KR20190130908A (en) | 2019-11-25 |
KR102072736B1 (en) | 2020-03-02 |
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